Self-propelling loader



- Aug. 5, 1941. w EHINGER 2,251,667

I SELF-PROPELLING LOADER Filed March 19, 1938 8 Sheets-Sheet 2 f/ VE/YTOR r WILLIAM E. EHINGER,

5, 1941- w. E. EHINGER 2,251,667

SELF-PROPELLING LOADER Filed March 19, 1938 8 Sheets-Sheet 5 f/YVE/YTOR WILLIAM EEHINGER,

Aug. 5, 1941. w. E. EHINGER SELF-PROPELLING LOADER Filed March 19, 1958 8 Sheets-Sheet 4 Now f/VVE/VTOR WILLIAM E-EH|NGER,

ATTX

Au 5, 1941. w. E. EHINGER SELF-PROPELLING LOADER 8 Sheets-Sheet 5 Filed March 19, 1938 4T:| F m J ATT'X [NVE/VTOR 'WILLIAM E. EHINGER,

Aug. 5, 1941. w. E. EHINGER I SELF-PROPELLING LOADER Filed March 19. 1938 8 Sheets-Sheet s //v VE/Y TOR I m W HMA EV B, M L H WW Aug. 5, 1941. w. E. EHlNGER SELF-PROPELLING LOADER 8 Sheets-Sheet 7 Filed March 19, 1958 wmm I; 7. I m l P N @Mfilfi f/WENTOR: WILLIAM E. EHiNGER,

cam ATTY NPN Patented Aug. 5, 1941 UNITED STATE SELF-PROPELLING LOADER William E. Ehinger, Tiifin, Ohio, assignor to The Jeflrey Manufacturing Company, a corporation of Ohio Application March 19, 1938, Serial No. 196,960

1 Claim.

This invention relates to a portable loader or conveyor of the self-propelling type which is particularly useful in loading loose material from a I storage pile into \a truck, as, for example, the loading of coal from a pile in a coal yard into a truck, though the machine is not restricted to this use and may be used to load other material such as gravel, crushed stone, etc.

An object of the invention is to provide a machine of the above type which is very flexible in operation and is very easily controlled to perform the loading operation.

Another object of the invention is to'provide safety means to control the downward movement of a boom which is adjusted by a hydraulic piston motor.

Other objects of the invention will appear hereinafter, the novel features and combinations being set forth in the appended claim.

Fig. 1 is a side elevational view of the apparatus comprising my invention;

Fig. 2 is a. front view showing particularly the mast of the loader of my invention;

Fig. 3 is a sectional elevational view taken on the line 3-3 of Fig. 1 looking in the direction of the arrows;

Fig. 4 is a longitudinal sectional view showing the construction of the hydraulic piston motor for adjusting the boom in the device of Fig. 1;

Fig. 5 is a plan view of the frame or strut of the device of Fig. 1 with numerous parts shown in section;

Fig. 6 is an elevational view taken on the line 6-3 of Fig. 5 looking in the direction of the arrows;

Fig. 7 is an enlarged side elevational view of the bottom or foot end of the boom of the device of Fig. 1;

Fig. 8 is a longitudinal sectional elevational view of the structure shown in Fig. 7;

Fig. 9 is a sectional view taken on the line 9-3 of Fig. 7 looking in the direction of the arrows;

Fig. 10 is an enlarged side elevational view of the head or discharge end of the boom showing also the attached chute of the device of Fig. 1

' of the drawings;

Fig. 11' is a view taken on the line of Fig. 10 looking in the direction of the arrows, with parts of the cylinder shown in section;

Fig. 12 is a sectional view taken on the line |2-|2 of Fig. 10 looking in the direction of the arrows;

Fig. 13 is an enlarged sideelevational view showing the mounting of the boom on the mast;

Fig. 14 is a view taken on the line |4-|4 of Fig. 13 looking in the direction of the arrows with parts broken away to show the'structure of one of the bearings;

Fig. 15 is an enlarged detail view showing in elevation the drive means for one of the traction wheels;

Fig. 16 is a sectional view taken on the line Iii-l6 of Fig. 15 looking in the direction of the arrows;

- Fig. 17 is an enlarged plan view of the drive and control mechanism for the traction devices;

Fig. 18 is a sectional and elevational view taken on the line Ill-l8 of Fig. 17 looking in the direction of the arrows;

Fig. 19 is anenlarged sectional veiw showing the bottom of the hydraulic piston motor for adjusting the boom and a control valve associated therewith;

Fig. 20 is a plan view of an improved hydraulic pump comprising a feature of my invention;

Fig. 21 is a side elevational view of the pump of Fig. 20 with parts shown in section;

Fig. 22 is a sectional view taken on the line 22-22 of Fig. 21 looking in the direction of the arrows;

Fig. 23 is a piping diagram for control system;

Fig. 24 is a sectional view of the control valve of the hydraulic system;

Fig. 25 is an end view of the valve of Fig. 24; I Fig. 26 is a view partly in plan and partly in section of a combined accumulator and pressure relief valve of the hydraulic system; and

Fig. 27 is an end view of the device of Fig. 26.

Referring particularly to Figs. 1, 2 and 5 of the the hydraulic drawings, it will be seen that the portable loader or scraper conveyor comprising my invention includes a main frame or strut 30 formed by a pair of spaced longitudinally extending inner channel members 3|, 3| and a pair of spaced outer channel members 32, 32 which, at their rear ends, are spaced apart from the channel members 3|, 3| and attached thereto by cross-pieces 33, 33 (see Fig. 2), the forward ends of said outer channel members 32,'32 converging inwardly toward said inner channel members 3|, 3| and being, attached thereto at their forward ends. At their rear ends the channel members 3|, 3| and 32, 32 are provided with upwardly extending brackets 34 between which extend a plurality of pipes 35,36 and 31. A transverse shaft 33 extends loosely through holes in the brackets 34 and through the aligned pipes 35, 33 and "which pipes act as spacers for the channel members 3|, 3| and 32, 32.. The shaft 33 carries ground engaging supporting and traction wheels 35 at opposite ends thereof, which wheels 35 act to support one end of the strut or main frame 55 and are employed to propel the loader, as hereinafter described in complete detail.

Extending upwardly from the rear end of the main frame or strut 35 and pivotally attached thereto for free movement about the axis of the shaft 35 is a mast 45 comprising spaced apart longitudinally extending inner channel members 4| 4| and spaced outer channel members 42, 42 (Fig. 2) which are spaced apart from the inner channel members 4|, 4| at their bottoms by the spacer pipes 35 and 31, said inner and outer channels 4|, 4| and 42, 42 beingattached together at their tops. A cross-channel 43 is provided intermediate the top and bottom of said mast 45 to brace the upwardly extending channel members 4 I, 42.

Pivotally. attached to the rear end of the main strut 35 and movable upwardly and downwardly between the inner channel members 4|, 4| of the mast 45 is a scraper conveyor mechanism I comprising a boom 44 formed by a pair of longitudinally extending upright side plates 45, 45

which are rigidly connected by a plurality of spaced apart intermediate cross-pieces 45 (see Fig. 3) and bottom cross-pieces 41. The side plates 45 are also reinforced by upstanding angle members 45, the bottoms of which are rigidly attached to said cross-pieces 41.

Extending longitudinally through substantially the entire length of the boom 44 and supported upon the cross-pieces 46 in a U-shaped trough or bottom plate 49. The side plates 45, 45 are provided with inwardly extending upper run guideways 55, 50 formed by spaced top and bottom angle plates and lower run guideways 5|, 5|. Adjacent the top of the boom 44 is a head shaft 52 provided with appropriate chain receiving rollers and adjacent the foot thereof is a similar shaft 53 provided with appropriate chain receiving rollers 54, 54 illustrated in detail in Fig. 9 of the drawings.

A pair of endless conveyor chains 55, 55 extends between the rollers 54, 54 associated with the tail shaft 53 and the similar rollers associated with the head shaft 52 and comprise the draft and guide means of the scraper conveyor mechanism associated with the boom 44 which is completed by a plurality of scraper cross-flights 55 which are rigidly attached to said chains 55, 55.

By reference to Figs. '1, 8 and 9 of the drawings, it will be seen that the foot of the boom 44 is formed by increasing the width of the side plates 45 to provide downwardly extending skirts which house the drive means for the conveyor chains 55, 55, as hereinafter. described in complete detail, and also carry a chain tensioning means-in the form of a transversely extending shaft 51 carrying a Pair of spaced rollers 55 adapted to receive the chains. 55, 55, said shaft 51 being carried in elongated slots 55 in said skirts and being adjustable by nut and bolt adjusting means 55.

The bottom edges of said plates 45 at said foot section are connected by an enclosing bottom plate 6| which terminates adjacent' a heavy wear plate 52 which also extends between said plates 45, 45 and is located at the bottom-most portion thereof and takes the wear of the lower end of the boom 44 which is adapted to rest upon the ground or material which is being elevated and conveyed. The wear plate 52 terminates adjacent an adjustable blade 53 which has a beveled leading edge 54 and which is pivotally attached to a pair of foot shoes or castings 55 by a transversely extending shaft 55. An operating lever 51 is provided for pivoting the blade 55 about the axis of the shaft 55 and is provided with a detent handle 55 adapted to be received by a selective one of the notches 55 in an arcuate retaining plate 15.

It is evident that by adjusting the lever 51 the blade 53 may be moved up and down about the axis of the shaft 55 to determine the attack of the boom on the material to be loaded. It is also possible to agitate the blade 53 during operation of the loader by releasing the detent and operating the lever 51 up and down. The aforementioned shoes or castings 55 provide a very effective protection means for the two conveyor chains 55 adjacent the foot or material gathering end of the boom 44 and also act to guide said chains as they move around the rollers 54, 54.

Access tothe area formed by the above mentioned skirts and side plates 45 is afforded by openings therein, one of which is seen at 1|, which openings are closed by removable plates, one of which is seen at 12.

Attention is now directed to Fig.9 of the drawings, and to the structure of the tail shaft assembly, which structure is similar to the assembly which includes the head shaft 52. As previously set forth, the shaft 55 is stationary and has mounted upon opposite ends, by appropriate journal bearings, the rollers 54 associated with chains 55. The opposite ends of the shaft 53 extend through appropriate openings in the side plates 45 and through plates 13 rigidly attached to said side plates 45 which increase the bearing area for said shaft 53.

The extreme ends of the shaft 53 are also provided with grooves 14 having flat bottoms which lie in the same plane and are adapted to receive retaining plates 15 which are removably attached by machine screws 15 and which operate to hold the shaft 53 rigid with the side plates 45, 45 of the boom and at the same time to prevent rotation thereof.

To form a protection for the shaft 53, it is surrounded with a tube 11 which is supported entirely and directly fromthe shaft 53 by means of a pair of spaced rings 15 which are tackwelded to said tube 11 and have a press fit with the shaft 53. The extreme ends of the tube 11 have welded thereto guide and protecting plates 13* which have apertures therein into which the hubs of the rollers 54 extend. To permit entirely free rotation of said rollers 54 a relatively small amount of clearance is provided between the plates 19 and said hubs and between the ends of the tube 11 and said hubs where they surround said hubs. As best seen by reference to Fig. 8 of the drawings, the tube 11 is positioned in contact with the trough or bottom plate 45 of the conveyor which is supported at this point by a transversely extending angle member 55.

Attention is now directed particularly to Figs 1 and 5 of the drawings, and to the drive for the above described conveyor mechanism associated with the boom 44. Mounted upon a platform 5| at the rear end of the main frame or strut 35 is an electric motor 52, though a gasoline motor may be employed if desired. The motor 52 drives a pivot shaft 53 through a small sprocket 54 mounted upon the shaft of said motor 52 and a large sprocket 55 keyed to said pivot shaft 53 which are interconnected by a than the rate of crowding movement.

I larly for movement from one place to another,

, relatively short drive chain 86. The close proximity of the motor 82 and the shaft 83 makes for a minimum length of drive chain 86 which is verydesirable due to the fact that said drive chain 89 is the highest speed drive chain in the entire driving system and, as is well known,

hi h speed chains tend to wear'out and cause pivotal connection with brackets 98, 88 which extend upwardly from the rear ends of channel members 3|, 3| and are provided with circular openings adapted to receive said bearing blocks The hub of the sprocket 95 is-provided with a pinion gear 89 which meshes with a large gear 90 carried by a jack shaft 9| in appropriate bearings 92, 92 in the side plates 45, 45. Loosely journaled on the jack shaft 9| is a drive pinion '93 which is controlled by a friction clutch 94 associated with jack shaft 9I and which meshes with a large gear 95' carried by knuckle shaft 96 mounted in bearings 91, 91 carried by side plates 45. The knuckle shaft 96 has keyed thereto a pair of drive sprockets 98 which mesh with-the previously described conveyor chains 55 to effect the final drive from the motor 82 to said conveyor chains.

By reference to Fig. 1 of the drawings, it will be seen that the clutch 94 is'provided with an operating lever 99 and it is evident that whenever motor 82 is running, the scraper conveyor may be operated to convey material from the foot to the head end of the boom 44 under the control of the operator through said lever 99 and clutch 94. In other words, by engaging said clutch 94 the conveyor will convey material, and by disengaging it the conveyor-will remain stationary. 4

As also seen by reference to Figs. 1, 7 and 8 of the drawings, the chains55 may be tensioned by the tensioning mechanism including the shaft 51 and the rollers 58 by virtue of their relation to the sprockets 98.

It may also be mentioned that the friction clutch 94 performs as a safety device in that in case of any overload on the conveyor mechanism this clutch will slip, thus preventing the breakage of any parts. The slipping of the clutch would be a signal to the operator that the conveyor is overloaded and the clutch should be disengaged.

It is desirable to operate the machine through the traction wheels 39 from the motor 82 in reverse directions and at different speeds. For example, to effect a crowding of the loader into a pile of material by crowding the foot or receiving end of the boom 44 into the material, it

-is desirable to feed the machine to the left, as

viewed in Fig. 1, by applying power to the tractiton wheels 39. This crowding-action should be at a relatively low speed to provide great power. Movement of the loader away from the pile of material under power is also desirable and in the interest of speed and economy of time, this rate of movement should be considerably higher I have found a ratio of three to one to be very satisfactory.

It is also desirable to be able to control the traction wheels 39 to swing the loader particu and to this end the control means for said traction wheels 39 may be operated to apply power to either of the traction wheels 39 selectively and simultaneously to apply a brake to the other one whereby the machine would swing about an upright axis in a relatively short radius.

Attention is now directed particularly to Figs.

, 5, 17 and 18 of the drawings. and to the driving means for said traction wheels 39. Loosely journaled on the previously described pivot shaft 83 is a sprocket I00 with which is associated a friction clutch IOI controlled by a lever I02 seen in Fig, 1 of the drawings. Extending rearwardly from the sprocket I00 is a chain I03 which is associated with the sprocket I04 keyed to a countershaft I05 journaled in bearings I05, I01 carried on'channels 3I and 32, respectively.

Feathered to the countershaft I05 and slidable along the axis thereof is a gear I08 adapted to be slid along said shaft I05 either to mesh with an idler gear I09 (see Fig. 6), which in turn meshes with the gear IIO keyed to a reversing shaft III, or to mesh'with a large gear II2 also keyed to said reversing shaft III, or to be in a neutral position where it meshes with neither the gear I09 nor the gear II2. It is manifest that when the gear I08 meshes with the gear I09 the shaft III will be rotated in one direction at a relatively fast speed and whenv the gear I08 meshes with the gear II2 the shaft III will be rotated in the opposite direction at a relatively low speed. This means provides for the reverse travel of the loader at different speeds, as above set forth.

The operating means for sliding the gear I08 is journaled upon a supporting plate II5 which in turn is supported by appropriate journals on the shafts I05 and I I I. It may also be mentioned that the lever II3 preferably has associated with it some means to designate and lock it in the neutral, forward andreverse positions of'adjustment to which it can be shifted.

Associated with the reversing shaft III is a pair of control clutches one for each of the traction wheels 39, 39 and these clutches include means in association therewith so that they are normally both in an engaging position and a single operating lever is provided so that said clutches may be selectively disengaged and simultaneously with the disengagement of any clutch a friction brake mechanism associated with the traction wheel 39 controlled by said clutch is applied,

Attention is now directed particularly to Figs. 5, 17 and 18 of the drawings and to the structure of this control mechanism. The reverse shaft III is mounted in journal boxes I I5, IIG carried by the channel members 3|. Near opposite ends of said shaft III and inwardly of said bearing boxes I I6 is a pair of similar jaw clutches H1 and H8. prises a clutch element or casting I I9 having integral teeth I20 meshing with a gear I2I carried upon a propelling shaft I22 carriedby journal boxes I23, I23 mounted on channel members 3| and 32. The clutch element H9 is journaled loosely upon the shaft III and has jaws I24 adapted to engage the jaws I25 of a cooperating clutch element or casting I26 which is feath- Each of said jaw clutches com-- into operating relation with the cooperating clutch elements I I9 thereof.

'Pivotally mounted upon a bottom plate I26 (see Fig. 18) which is carried by the frame 30 by pivot bolts I 29 and brackets I30, I30, is a yoke I 3I which terminates in an operating lever I32 to which is attached an operating rod I33 which in turn is controlled by control lever I34 (see Fig. 1) located at an operator's station with all of the other control levers including previously described levers 99, I02 and H3. Associated with each of the clutch elements or castings I26 is a shipper I35 which is pivotally connected to the yoke I3I by straps I36.

It is manifest by reference to Figs. and 17 of the drawings that if the lever I32 is moved laterally, as viewed in these drawings, the clutch element I26 of the clutch II6 will be disengaged while the clutch II1 remains in engaged relation. Movement of the lever I32 in the opposite direction will effect disengagement of the clutch I I1 while the clutch I I6 remains engaged. When the lever I32 is in the normal position both the clutches H1 and H6 will be in engaged relation.

To provide for the application of a braking action to the propelling shaft I22 whenever the clutch associated therewith is disengaged, thereby to effect a rapid turning of the loader, I associate with each of said shafts I22 a braking mechanism, said mechanism being seen at I31 and I31. Said mechanisms are of similar construction and the structure thereof can be readily seen by reference to Figs. 1'1 and 18 of the drawings. As there illustrated, each shaft I 22 carries a brake drum I36 with which is associated a brake band I39, adjustably attached at one end to a stationary bolt I40 and attached at the other end to an adjusting bolt I. The bolt III is associated with a pivoted lever I42 pivoted on a shaft I43 which extends between the two braking mechanisms I31 and I31 and is supported from bottom plate I26 by journal boxes I44. The front end of the lever I42 rests upon and is operated by a horizontal arm I45 of a bell crank lever which also includes a 'vertical arm I46 pivotally attached to the shipper I35 and further includes a cylindrical bearing portion I41 by which it is pivotally mounted, which bearing portion I41 is carried on an appropriate pivot bolt I46 carried by bracket I30 and I49.

.It is thus evident that, whenever clutch H6 is operated to a disengaged position thereby to release the normally established drive from reversing shaft III to the associated propelling shaft I22, the brake mechanism I 31' associated with said clutch II8 will also be operated to restrict or prevent rotation of said shaft I22 while the entire drive from reversing shaft III will be effected through clutch II1 to the associated propelling shaft I 22. I To provide for the movement of one of the clutch elements or castings I26 while the other remains in its normal position, each of said ments I26. This structure is, of course, necessary to provide for the selective operation of the clutches I I1 and II 6 by the single yoke I3I.

The final drive from the propelling shafts I22 to the traction wheels 39 is effected by sprockets or pinions I5I keyed to said shafts I22 which mesh with teeth I52 (see Figs. 15 and 16) removably attached to the rims of said wheels 39. It is to be particularly noted by reference to Figs. 15 and 16 of the drawings that the teeth I52 are all individual and form a ring gear with the rim of said wheel 39 by being individually attached thereto by rivets I53. This makes for a very inexpensive and easily replaceable gear structure, particularly in view of the fact that should any tooth become worn, broken or damaged, that single tooth may be replaced without requiring the replacing of an entire ring gear as is usual with a common type of cast ring gear construction.

Attention is now directed particularly to Figs. 13 and 14 of the drawings and to the structure of the sliding connection which is effected between the guide mast 40 and the boom 44 and the safety mechanism which limits the downward movement of the boom 44 to relatively short steps. Extending downwardly from the outsides of the side plates 45 is a pair of plates I54, I54 having forward and rearward pairs of aligned apertures I55 adapted to receive selectively a cross shaft I56 received in spacer pipes I51 between which is pivotally attached a block I59 of an extensible hydraulic motor or jack I59, hereinafter described in complete detail.

Attached to the plates I54 are appropriate journal plates I60 which increase the bearing area between said shaft I56 and boom 44. Each end of the shaft I56 receives a machine screw I6I having a washer I62 thereon which screw I6I inner channel member 4| of the mast 40. This structure provides for relative up and down movement of the boom 44 with respect to the mast 40 while at the same time effecting a guiding of said boom by said mast. It is evident that the shaft I56 may extend through either the upper pair or lower pair of aligned apertures I55 to adjust the maximum and minimum heights of the head end of the boom 44.

To provide a safety feature which precludes a falling of the boom 44 I provide a plurality of ledges or detents I63 on the front face of each of the channels 4I. Journaled loosely on opposite ends of the shaft I56 between the plates I54 and the channels 4| is a pivoted lever I64 which levers I64 are connected together by a cross shaft I65 to which is attached a coil spring I66 which, in turn, is attached to one of the plates I64. The coil spring I66 tends to rotate the levers I64 in a clockwise direction.

Welded to the outer top portion of each of the levers I64 is a pawl I 61 adapted to ride on the front face of a channel II. It will be evident that the spring I66 will maintain the pawl I61 in contact with said channel H and that downward movement of said boom 44 will be impeded when I ever a pawl I61 strikes an upstanding detent I63. As a consequence, the maximum distance the boom 44 could fall would be from one detent I63 to the succeeding detent.

To-provide for the normal downward movement of said boom 44, as hereinafter described, the pawls I61 may be released -by rotating the levers I64 which are connected together by the cross shaft I65, as above described, in a counter- It is manifest that the afore-described safety mechanism will automatically return to a safety position whenever released and that it is necessary for the operator to release said safety mechanism whenever the boomis to be lowered any appreciable amount. 1

As previously set forth, I provide a hydraulic motor or jack I59 for raising and lowering the discharge end of the boom 44 which has been found to be very efficient, particularly due to the ease and smoothness with which it can be operated and adjusted to any desired position in very small steps and can be locked in any desired position of adjustment. This structure furthermore eliminates entirely the necessity for ropes or cables which are liable to break and simplifies very appreciably both the structure of the boom elevating mechanism and the mast which must support it.

Said hydraulic motor or jack I59 comprises a heavy base I10 (see (Fig. 19) which receives a transverse pivot pin I1I carried by a pair of arms I12 (see Fig. welded to the previously described pipe 36 carried by shaft 38. Welded to the base I10 is a main cylinder I13 to the top of which is threaded a sleeve I14 (see Fig. 4) below I which is a spacing sleeve I15. Within the main cylinder I13 is a secondary cylinder I16 provided with a piston head I 11 and a washer I18. The spacing sleeve I15 insures adequate telescoping of the cylinders I13 and I16 to insure their rigidity against lateral flexing or bending. The head I11 is provided with a central bore I19 to allow the hydraulic fluid under pressure which is introduced into said cylinder I13 to pass into secondary cylinder I16. Associated with the secondary cylinder I16 is a piston rod I80 the upper end of which'is rigidly attached to the previously described block. I58 (Fig. 14). The rod I80 is provided with a piston head I8I and a washer I82, as shown in Fig. 4.

The previoulsy described base I10 (Fig. 19) for the main cylinder I13 is provided with a fluid inlet port I83 with which is associated a fitting I84 and a ring I85 having a central opening I86 and a plurality of bores I81. Associated with the central opening I88 is a check valve comprising a ball I88 and a compression spring I89. Associated with the fitting I84 is a pressure supply pipe I90.'by which hydraulic fluid is supplied to the hydraulic motor or jack I59. Whenever hydraulic fluid is supplied to the pipe I90 liquid will flow through the bores I81 and through the opening I88 and unseat the ball I88 whereby said fluid will flow relatively free through port I 83 into the main cylinder I13.

During the first period of application of hydraulic fluid to said main cylinder I13, the secondary cylinder I16 (Fig. 4) will move upwardly in unison with the rod I80 due to the fact that the area of the piston head I11 is greater than the area of the piston head I 8|. After the secondary cylinder I16 has been moved to the limit of its movement as determined by the spacing sleeve I15, additional application of hydraulic fluid will cause the rod I80 to move with respect to the secondary cylinder I16 whereby the hydraulic jack will progressively expand, the expansion first being through the secondary cylinder I16 and finally through the rod I80. When the hydraulic fluid is drained from the motor or jack I59 a reverse action will take place and the rod I80 will move downwardly to the limit of-its stroke in the secondary cylinder I18 after which the secondary cylinder I18 will move downwardly with respect to the main cylinder Due to this downward movement of the boom 44 during which the hydraulic motor or jack collapses it is desirable that the rate of downward movement be restricted as the force thereon is relatively great due to the weight of the boom 44. This is effected by the check valve including the spring I89 (Fig. 19) and ball I88 which operate to close the opening I86 in response to a flow of fluid from the main cylinder I13. As a consequence, the hydraulic liquid is required to flow from said cylinder I13 only through the restricted bores I81 which, due to their sm ll area, limit the speed of downward movement of said boom 44. Furthermore, as above set forth, should anything break in connection with the hydraulic motor or jack I59 which would tend to drop the boom 44 this would be prevented by the safety mechanism above described, including the detents I63 and pawls I61.

Adjacent to the top or discharge end of the otally attached, as illustrated in Fig. 10 of the drawings, by angle members I92 to brackets I93 carried on the bottom of the boom 44.- Said chute I9I includes a forward screen section at I94 which discharges into an adjustable slack chute I95 pivotally attached to said chute I9I and carried by chains I96.

Novel means are provided, however, forthe aforementioned adjustment of said chute I9I and comprise a hydraulic piston motor I91 comprising a cylinder I 98 attached to a plate I99 which, in turn, is supported by appropriate forward angle members 48 and cross-angle members 208. Within the cylinder I98 is a piston 200 to which is attached a piston rod 20I having a head 202 attached to a pair of operating links 203, 203 by a pivot bolt 204. The opposite ends of the links 203 are pivotally attached to a drawbar 205 formed by a pair of spaced angle members and attaching cross-angles, which drawdraulic piston motor I91 is controlled by avalve adjacent the operator's position which valve also controls the previously described hydraulic jack or motor I59 thereby providing for the ready adjustment of both the boom 44 and the chute I 9I by an operator without requiring his leaving his normal operating station and which adjustment can be effected to a large plurality of desirable positions in a very easy and highly efllcient manner.

Attention is now directed to Fig. 23 of the drawings, which illustrates diagrammatically the hydraulic system for controlling the boom 44 and the chute I9I. Said system includes a tank 2III which, as seen in Fig. of the drawings, is supported on a channel member 3I, which tank 2I0 acts as a reservoir for the hydraulic fluid. A feed pipe 2 leads from the bottom of said tank 2I9 to a pump 2I2 from which leads a pressure pipe 2I3. The pump 2I2 is preferably of a spe cial structure comprising a feature of my invention which is hereinafter described in full detail.

Connected between the feed pipe 2 and the pressure pipe H3 is a combination accumulator and pressure relief valve 2I4 hereinafter described in full detail. The pressure pipe 2 I 3 leads to a common control valve 2I5, hereinafter described in full detail, which has four positions of adjustment to control separately and individually the expansion and contraction of the hydraulic jack or motor I59 and the expansion or contraction of the hydraulic motor i91. From said control valve 2I5 a feed pipe 2I6 leads to the hydraulic motor or jack I59 and another feed pipe 2" leads to the hydraulic motor I91. A return flow pipe 2I8 also leads from the control valve 2I5 to the tank 2"! by way of pipe 2I I.

The structure of the control valve 2I5, is disclosed in Figs. 24 and 25 of the drawings, and comprises a casing 2I9 having a cylindrical bore 220 within which is rotatably mounted a cylinder or valve element 22I having an operating shaft 222 adapted to receive an operating handle 223. A threaded journal sleeve and packing gland 224 provides a bearing for the shaft 222 and is threaded into the casing 2I9, and is adapted to press against packing 230 to provide a seal for the cylinder 22I. Said casing 2I9 is provided with four ports 225, 226, 221 and 228 which are connected with the pipes 2I3, 2I6, 2I8 and 2I1, respectively. The cylinder or valve element 22I is provided with a bore 229 having openings substantially ninety degrees apart to align selectively with pairs of the ports 225, 226, 221 and 228 or to be positioned intermediate any two of said ports.

By reference to Figs. 23 and 25 of the drawings, it is to be noted that the handle 223 of said control valve 2I5 has four operating positions. In the position marked Chute down the valve 2I5 will connect ports 228 and 221 through bore 229 as shown in the full line position in Fig. 23, to allow fluid in the hydraulic piston motor I91 to flow freely into the tank 2III thereby to allow chute I9I to move downwardly. By rotating the handle 223 in a clockwise direction through ninety degrees to the position designated Chute up, ports 228 and 225 are connected by way of bore 229 whereupon hydraulic piston motor I91 is connected to the pressure pipe 2I3 and the chute I9I will be elevated. Further rotation of the handle 223 ninety degrees to the position marked Boom up connects ports 225 and 226 by way of bore 229 whereby pressure pipe 2 I3 is connected with hydraulic jack or piston motor I59 to elevate the boom 44. Still further rotation of the handle 223 through ninety degrees to the position designated Boom down connects the ports 226 and 221 by way of bore 229 thereby connecting hydraulic piston motor or jack I59 with the return flow pipe 2I8 to provide for downward movement of the boom 44.

It is furthermore to be noted that the handle 223 may be positioned substantially intermediate any one of the four above mentioned positions and when in any of said positions of adjustment the bore 229 will not afford communication between any two of the ports 225, 226, 221 or 228, as a consequence of which the hydraulic piston motor I91 and the hydraulic piston motor or jack I59 are locked in their position of adjustment. It is thus evident that a single control valve has been provided to control the operation of the entire hydraulic system including the two hydraulic motors I59 and I91 both to expand and contract them entirely independently and to lock either one or both of them in adjusted position.

By reference to Fig. 1 of the drawings, it is also to be noted that the control handle 223 for the valve 2 I5 is located at the operators position so that the hydraulic system may be controlled to adjust either the boom 44 or the chute I! or both of them without requiring the opera tor to leave his operating station. This, of course, makesfor great flexibility and ease of operation of the loader.

Attention is now directed particularly to Figs. 26 and 27 of the drawings, showing the construction of the combined accumulator and pressure relief valve 2I4 which, for brevity, will be referred to hereinafter as an accumulator. Said accumulator comprises a main body or casting 23I having top and bottom spring receiving bores 232, 232 and a central piston receiving bore 233. Within the bore 233 is a piston 234 attached at its rear end to a cross-head 235 carrying similar elongated upper and lower bolts 236 with which are associated composite coil springs 231 provided with head and intermediate seats 238, the intermediate seats 238 being employed to reduce the necessary length of the coil springs 231. It is evident that the two composite coil springs 231 urge the piston 234 to the left, as viewed in Fig. 26 of the drawings.

Communicating with the left-hand end of the bore 233 is the pressure pipe 2I3. It is thus evident that the pressure in said pipe 2I3 will be transmitted to the bore 233 and will urge said piston 234 to the right, as viewed in Fig. 26 of the drawings, against the action of the springs 231.

As hereinafter described, the pump 2I2 is of the reciprocating type which means that the hydraulic pressure supplied thereby to pressure pipe 2I3 will be of a pulsating character. The accumulator 2I4 will smooth out these pulsations due to the fact that piston 234 will move to the right under each pulsation and store energy in the coil springs 231 which will thereby urge the piston 234 to the left as the pressure of each individual pulsation is reduced, thus making the pressure in said line 2| 3 much more even or smooth than it would normally be.

The accumulator 2 also acts as a pressure relief valve by virtue of the fact that a port 239 leads to the bore 233 substantially intermediate the ends thereof and whenever the pressure in line 2I3 is sufflcient to move the cylinder 234 to the right, as viewed in Fig. 26, a sufficient amount to uncover said port 239 a by-pass circuit will be provided from the pressure pipe 2I3 to the feed pipe 2| I because said port 239 is connected to said pipe 2 by a branch pipe 246, as clearly illustrated in Fig. 23 of the drawings.

Attention is now directed to Figs. 5, 20, 21 and.

22 and to the structure of the pump 2I2. Said pump 2l2 comprises a main casting 24! which is supported on the bottom plate I28 and is provided with a cylindrical bore 242 which receives a removable cylinder 243. The bottom of the bore 242 has communication by way of port 244 with the pressure pipe N3, the port 244 being con trolled by check valve 245 which permits fluid to flow from said bore 242 to said pressure pipe 2I3 but prevents flow in a reverse direction. Reciprocally mounted within the cylinder 249 is a piston 246 having a head 241 pivotally attached to straps 248 by means of pin 249 held in place by removable cotter keys 2501 The cylinder 242 is provided with an elongated neck portion 25! which, due to its'decreased exterior diameter, provides a shoulder 252' against which abut-s a coil spring 253 which abuts the head 241 at its opposite end. This spring performs the double function of maintaining the cylinder 243 seated in the bore 242 and urging the piston 246 out of said cylinder 243.

The pump 2l2 is not provided with a check valve on the intake side but in lieu thereof I provide a circumferential chamber 254 in the main casting 24! which communicates with four radial ports 255 in the cylinder 243 and positioned so that said ports 255 communicate with the interior of said cylinder 243 when the piston 246 reaches the upper or outer extremity of its stroke. The chamber 254 is connected with the feed pipe 2!! whereby the hydraulic fluid will be supplied to said pump 2l2 from the reservoir 2! 0.

The main casting 24! is provided with a pair of integral rearwardly extending arms- 256 and 251 the latter of which is considerably larger than the former and extends upwardly and is provided at its upper end with a journal bearing 258 which supports one end of the countershaft I05 which drives said pump 2l2, as clearly illustrated in Fig. 5 of the drawings. Keyed to said countershaft I05 is an eccentric 259 which rides on a roller 260 carried between spaced arms 26!,

26! by a pin 262, which spaced arms 26! are pivotally attached at their lower rear ends by a cross-pin 263 to the rearwardly extending arms 256 and 251 of the main casting 24! and are pivotally attached at their forward ends by pins.

264, 264 to the straps 248, 248. The arm 251 is also preferably provided with an elongated arcuate opening 265 with which the pin 262 is always in alignment to permit ready removal of said pin.

From the above description of the construction of the pump 2l2 it is manifest that whenever countershaft I05 rotates the eccentric 259 will rotate on the roller 260 which will cause reciprocal movement of the arms 26! about the axis of pin 263 which reciprocal movement will be transmitted to the piston 246 by way of straps 249 and head 241, This movement of the piston 241 is positive in one direction which is in the direction of pressure creation and is non-positive in the opposite direction under the influence of the coil spring 253.

In order to prevent reciprocation of the piston 246 with the consequent building up of pressure in the hydraulic system for no useful purpose when neither of the hydraulic piston motors I59 or I91 is in operation, I provide means con structed normally to maintain the piston 253 in the position illustrated in Figs. 21 and 22 of the drawings in which the coil spring 253 is compressed which provides for free rotation of the eccentric 259. In other words, I prevent the roller 260 followlngthe cam 259 except when hydraulic fluidunder pressure is desired for a useful purpose. To this end I provide a detent 266 which has a tapered nose and is adapted to engage one of the arms 26! and prevent return movement of it. thereby holding the piston 246 in its extreme downward position.

The detent 266 is provided with a shank 261 which extends through a bored boss 269 formed integral with the arm 251 and containing a coil spring 269 which presses on the detent 266 urging it into a position to hold one of the arms 26! in a locked non-operating position, as above described. The shank 261 is provided with a removable head 210 which limits the movement of the detent 266 under the influence of the spring 269. The head 210 is bifurcated to receive an operating lever 21! whichv is pivotally attached thereto by a pin 212 the bottom of which lever 21! is pivotally attached by a pin 213 to a bracket 214 mounted upon the bottom plate I28.

The lever 21! is positioned adjacent to the other operating levers at the operators position, as clearly illustrated in Fig. 1 of the drawings. It is manifest that whenever the lever 21! is in its normal released position the detent 266 will engage one of the arms 26! and hold the pump 2I2 in a non-operating position. Whenever it is desired-to operate either of the piston motors I 59 or I91 the lever 21! will be moved to the left, as viewed in Fig. 22 of the drawings, whereupon the pump 2l2 will be brought into operation to create the necessary fluid pressure.

In addition to the structure which has previously been described, it may be mentioned that the main frame or strut 30 is provided with ;a removable cover 215 (see Fig. 1) to protect the operating mechanism mounted thereon. The cover 215 is provided with appropriate apertures through which the operating levers I02, II3, I34, 223 and 21! extend.

To start the machine for operation the clutches 94 and I0! (see Fig. 5) should be in a disengaged position and the gear shift lever I I3 should be in the neutral position.- The motor 62 is then started. To putthe conveyor mechanism in .operation the lever 99 is operated to control the friction clutch 9 4 which, as above set forth, acts as a safety device in case of an overload, by slipping.

To crowd the lowered gathering or foot end of the boom 44 into a pile of material thereby to load -said'material the lever H3 is operated to engage the gears I09 and H2 which, as above set forth, effects a low speed feeding drive of the loader in the left-hand direction, as viewed in F1g. 1 of the drawings. Thereafter, lever I02 is operated to engage clutch I 0! which controls the completion of the drive from the motor 82 to the traction wheels 39 to effect the above mentioned crowding action.

I'o reverse the direction of movement of the loader away from the pile of material, the clutch I 0! is disengaged by the operation of lever I02 and the gear shift lever H3 is moved to reverse position in which gears I06 and I09 are in mesh or a reverse operation it is only necessary to operate the control lever I34 which is effective to disengage the drive to one of the traction wheels 39 and simultaneously to apply the brake thereto. It is manifest that reverse swinging movement of the loader can be effected by a reverse movement of the control lever I34.

To raise the boom 44 or the chute ISI it is first necessary that the machine be stationary and that the gear shift lever H3 be in neutral position. With this condition the handle 223 for the control valve 2l5 is moved to the desired position of adjustment such as Boom up or Chute up," whereupon clutch lever I02 is operated to engage clutch IM. This will cause rotation of the countershaft I05 but pressure will not yet be available until lever 21! is operated to release the detent 266 and place the pump 2|! into operation. The prescribed operation will then take place until the, lever 21! is released which will automatically render the pump 2|2 non-operating. To lower the boom 44 or the chute [9| all that is necessary is to move the handle 223 of control valve 2l5 to the proper designated position.

Whenever said handle 223 is in any intermediate position between the four operating positions, as above set forth, both the hydraulic jack or piston motor I59 and the hydraulic piston motor I91 will be locked in adjusted position.

It is manifest that the portable loader is extremely flexible in that practically any adjustment thereof can be effected by the operator from his normal operating station and that a minimum of effort is required to effect a wide range of adjustments and movement of the machine either for transportation from one pile of material, such as coal, to another, or for operating on a pile of coal or loading it into a truck.

It is furthermore to be noted that there is a minimum of wear on the elements of the hydraulic control system because the pump 2I2 is rendered inoperative except when it is required to do useful work. This eliminates entirely the circulation of hydraulic fluid, such as oil, for no useful purpose, and increases the life of the oil as well as the life' of the equipment.

Furthermore, the safety feature for the boom 44 insures against the boom falling, as the downward movement thereof is restricted to very short distances by the detents I63 and pawls I61. It may be stated that whenever a pawl I61 rests on a detent I63 it is usually necessary to elevate the boom a slight amount by the hydraulic jack or piston motor I59 to release said pawls I61 from said detents I63.

Furthermore, by reference to Fig. 1 of the drawings, it is to be noted that the top of the mast 40 is in a position substantially always below the boom 44 except when the boom is in its lowermost position, which even then, due to the curved path of travel of the mast top, is only slightly above the top of the ,boom, as illustrated in dotted lines. The loader is thus free to pass under low head structures.

Certain other features herein disclosed are also disclosed and claimed in my application for a Self-propelling loader, Serial No. 196,961, filed March 19, 1938. This includes particularly the truck propelling control mechanism and the elements which go to make up this propelling mechanism as well as the drive mechanism for the scraper conveyor and the propelling mechanism.

Obviously those skilled in the art may make various changes in the details and arrangement of parts without departing from the spirit and scope of the invention as defined by the claim hereto appended, and I therefore wish not to be restricted to the precise construction herein disclosed.

Having thus described and shown an embodiment of my invention, what I desire to secure by Letters Patent of the United States is:

In a portable loader, the combination with a frame, of a boom connected thereto, a mast for guiding said boom for up and down adjustment relative thereto, means for adjusting the boom relative to said mast, releasable latch mechanism between the boom and the mast for enabling said boom to be supported on said mast, and manually operable mechanism extending along said boom from said latch mechanism to enable the operator to release said latch mechanism preparatory to the lowering of said boom by control of said boom adjusting means.

WILLIAM E. EHINGER. 

